Libby Purves has been dropped as the chief theatre critic of the Times after three years at the paper.

Purves, who also presents Midweek on BBC Radio 4, told theatre publicists that her departure from the Times "is not my decision in any way".

In a message to one publicist, Purves said that the Times editor John Witherow had "decreed that he does not want me to continue as chief theatre critic" and added: "This is not my decision in any way. At all."

Purves joined the Times as its chief theatre critic in 2010 after an acclaimed broadcasting career spanning three decades. She joined the BBC in 1971 and went on to become the first woman to present Today on Radio 4. Since 1984, she has presented Radio 4's Midweek, and in 1999 was awarded an OBE for services to journalism.

In a message responding to well-wishers on Twitter, Purves suggested she did not know why she was being let go by the Times: "Thanks, kind theatre-tweeple. No, not a joke. No, no idea why. Ends Oct 11.Shall not vanish from back row opining, watch this space."

Her departure was met with surprise and dismay from the arts world, which has watched the number of national newspaper critics reduce dramatically in recent years.

"It's a real shock to everyone in the industry. Unfortunately arts criticism is becoming a minority interest in the eyes of newspaper owners," said Kevin Wilson of Kevin Wilson Public Relations, which has promoted stage shows including The Rocky Horror Show and Joan Rivers's A Work in Progress By a Life in Progress.

Last month the Independent on Sunday axed a number of its high-profile arts critics, including the music writer Simon Price and film reviewer Nicholas Barber, in a move away from comprehensive reviews of music, stage, film and books.

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